Classic potential at elegant Henri

In this economy, when even the likes of chefs Grant Achatz and Graham Elliot are on the verge of opening casual eateries, it's no small feat to debut a white-tablecloth dining salon with a tony Michigan Avenue address to match.

But that's exactly what Irish restaurateur Billy Lawless and chef Dirk Flanigan of the Gage attempt with next-door neighbor Henri, which swiftly claimed popularity after opening in August for dinner and September for lunch.

The 65-seat space—named for the building facade's architect, Louis Henri Sullivan—emanates a restrained luxury that's old-world romantic and elegant. Dark brown velvet walls set off stately chairs covered in cool, pale green; sheer white floor-to-ceiling curtains screen the distracting rush of traffic while allowing a wash of light and the veiled suggestion of Millennium Park across the street. Amply spaced tables with smooth tablecloths and simple vases of white flowers lend a dignified mood that's quiet but not buttoned-up.

The menu is similarly graceful. Mr. Flanigan's classic, largely French-inspired dishes don't aim to surprise, just please, and at lunch, the focus of this review, he's reasonably successful.

Uneven execution may be a sticking point at the moment. Refrigeration stunted the flavor of a $12 plate of organic heirloom tomatoes; they arrived chilled, with underseasoned herb vinaigrette. Vegetable Napoleon—a stack of potato, tomato, squash, eggplant and beet slices ($22)—is accompanied by robustly sweet and savory tomato-pepper jam, but the veggies themselves were a bore.